Re: [PATCH 05/34] tools lib bpf: Add missing bpf map functions

[Arnaldo Carvalho de Melo]

Em Thu, Nov 17, 2016 at 11:23:58AM +0800, Wangnan (F) escreveu:
> 
> 
> On 2016/11/15 12:05, Wang Nan wrote:
> >Add more BPF map operations to libbpf.
> >
> >Signed-off-by: Wang Nan <wangnan0@xxxxxxxxxx>
> >Cc: Alexei Starovoitov <ast@xxxxxx>
> >Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
> >Cc: Li Zefan <lizefan@xxxxxxxxxx>
> >---
> >  tools/lib/bpf/bpf.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++++
> >  tools/lib/bpf/bpf.h |  7 +++++++
> >  2 files changed, 63 insertions(+)
> >
> >diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
> >index 4212ed6..e966248 100644
> >--- a/tools/lib/bpf/bpf.c
> >+++ b/tools/lib/bpf/bpf.c
> >@@ -110,3 +110,59 @@ int bpf_map_update_elem(int fd, void *key, void *value,
> >  	return sys_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
> >  }
> >+
> >+int bpf_map_lookup_elem(int fd, void *key, void *value)
> >+{
> >+	union bpf_attr attr;
> >+
> >+	bzero(&attr, sizeof(attr));
> >+	attr.map_fd = fd;
> >+	attr.key = ptr_to_u64(key);
> >+	attr.value = ptr_to_u64(value);
> >+
> >+	return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
> >+}
> >+
> >+int bpf_map_delete_elem(int fd, void *key)
> >+{
> >+	union bpf_attr attr;
> >+
> >+	bzero(&attr, sizeof(attr));
> >+	attr.map_fd = fd;
> >+	attr.key = ptr_to_u64(key);
> >+
> >+	return sys_bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr));
> >+}
> >+
> >+int bpf_map_get_next_key(int fd, void *key, void *next_key)
> >+{
> >+	union bpf_attr attr;
> >+
> >+	bzero(&attr, sizeof(attr));
> >+	attr.map_fd = fd;
> >+	attr.key = ptr_to_u64(key);
> >+	attr.next_key = ptr_to_u64(next_key);
> >+
> >+	return sys_bpf(BPF_MAP_GET_NEXT_KEY, &attr, sizeof(attr));
> >+}
> >+
> >+int bpf_map_pin(int fd, const char *pathname)
> >+{
> >+	union bpf_attr attr;
> >+
> >+	bzero(&attr, sizeof(attr));
> >+	attr.pathname = ptr_to_u64((void *)pathname);
> >+	attr.bpf_fd = fd;
> >+
> >+	return sys_bpf(BPF_OBJ_PIN, &attr, sizeof(attr));
> >+}
> >+
> >+int bpf_map_get(const char *pathname)
> >+{
> >+	union bpf_attr attr;
> >+
> >+	bzero(&attr, sizeof(attr));
> >+	attr.pathname = ptr_to_u64((void *)pathname);
> >+
> >+	return sys_bpf(BPF_OBJ_GET, &attr, sizeof(attr));
> >+}
> 
> bpf_map_{pin,get} should be rename to bpf_obj_{pin,get} since they can
> be used on BPF program. Thanks to Joe Stringer.

Ok, and keep:

+int bpf_map_lookup_elem(int fd, void *key, void *value);
+int bpf_map_delete_elem(int fd, void *key);
+int bpf_map_get_next_key(int fd, void *key, void *next_key);

as-is?

I'll push te first four patches in this series, will continue after
clarifying this one.

- Arnaldo

 
> >diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
> >index e8ba540..5b3e52b 100644
> >--- a/tools/lib/bpf/bpf.h
> >+++ b/tools/lib/bpf/bpf.h
> >@@ -35,4 +35,11 @@ int bpf_load_program(enum bpf_prog_type type, struct bpf_insn *insns,
> >  int bpf_map_update_elem(int fd, void *key, void *value,
> >  			u64 flags);
> >+
> >+int bpf_map_lookup_elem(int fd, void *key, void *value);
> >+int bpf_map_delete_elem(int fd, void *key);
> >+int bpf_map_get_next_key(int fd, void *key, void *next_key);
> >+int bpf_map_pin(int fd, const char *pathname);
> >+int bpf_map_get(const char *pathname);
> >+
> >  #endif
>